to make the choke/unchoke cycles a little faster

by only sending new peers, as in ut_pex.
Track connected time and last pex sent time, and only send
peers connected since the last sent time.
Usually, there are no new peers, so now we don't send a message at all.
Also, don't send PEX to seeds after the handshake.

Implement variable timeout
Hardcode handshake bytes
Log tweaks

Linting dep-ann: Added @Deprecated annotations in i2psnark, i2ptunnel, ministreaming, routerconsole, streaming

reorder some logging
volatile

untested

   - Make I2PSocketFull.close() nonblocking; it will now cause any user-side
     writes blocked in I/O (Connection.packetSendChoke()) to throw
     an exception (tickets #629, #1041)
   - Don't ignore InterruptedExceptions; throw InterruptedIOException
   - Back out static disconnect exception
   - MessageInputStream locking fixes
   - Cleanups
 I2PSnark:
   - Close socket before closing output stream to avoid blocking in
     Peer.disconnect(), and prevent Peer.disconnect() loop

   - Set unique tunnel nickname for additional instances
   - Increase page size to 50
   - Restore 1-arg SnarkManager constructor for compatibility
   - Add note about DHT file w/ multiple instances, to be fixed
   - Log tweak

- Change DHT from option bit to extension message
- Add DHT start/stop code
- Add UI for DHT enabling
- Add raw datagram protocol type and use for response port

   - Store received chunks in temp files
   - Don't allocate from heap for unneeded chunks
   - Remove peer count restriction for torrents with large pieces
   - Use priorities and rarest calculations to sort partials
   - Preserve p parameter in clear messages link

Handle announce URLs with parameters correctly

- Disable KRPC
- Shorten tracker string

  - Update session options when max bandwidth changes
  - BufferedStream cleanup and comments
  - torrent name display tweak
  - findbugs

- Better BEValue.toString()

(most of the following got missed in the last checkin)
- Fix about 9 NPEs
- Fix numwant in magnet mode
- Send metadata size in extension handshake
- Open trackers are primary if we don't have primary trackers
- Add missing break in port message handling
- Increase max msg size to account for metadata msg
- Remember magnets across restarts
- Drop peers w/o extensions if we need metainfo
- Fix DATA messages
- Fix tracker transition to non-magnet
- Fix infohash for non-magnet
- Fix up peer transition to non-magnet
- More logging

- Announce peers to local tracker
- Ping node on port reception
- More info on directory pages
- Cleanups

- Record the metadata bandwidth
- More null announce handling
- Callbacks for got MetaInfo event
- Cleanups